The present invention relates generally to orthopedic devices, and more particularly to orthopedic walker boots for supporting and/or immobilizing the lower limb of a wearer during activity.
Orthopedic walker boots are designed to be worn on the lower limb of a person afflicted with a lower leg, ankle, or foot injury, such as a fracture, soft tissue injury, or the like. The walker boot immobilizes and supports the injured lower limb during low-impact, weight-bearing activities such as walking and standing. The walker boot is often an effective substitute for a conventional plaster or fiberglass cast with numerous advantages. Among its advantages, walker boots are prefabricated yet are adaptable to different sized individual wearers or to variations in size of the same lower limb of a wearer over time as the lower limb is rehabilitated. In addition walker boots are more wear resistant, more comfortable to wear, and more easily cleaned than conventional casts and can be temporarily removed by the wearer for bathing, sleeping, range of motion exercise, or other non-weight-bearing activities.
Many orthopedic walker boots are known in the prior art as evidenced by the following representative U.S. Pat. No. 5,078,128 to Grim et al., U.S. Pat. No. 4,771,768 to Crispin, U.S. Pat. No. 4,572,169 to Mauldin et al., U.S. Pat. No. 4,057,056 to Payton, and U.S. Pat. No. 3,955,565 to Johnson, Jr. All of these prior art orthopedic walker boots are commonly characterized as having a rigid external shell which is the primary structural support for the lower leg, ankle, and foot of the wearer. The external shell is characterized as having either an open-heel or a closed-heel configuration. Mauldin et al. is an example of an open-heel configuration while Grim et al. is an example of a closed-heel configuration.
The open-heel configuration of the external shell exemplified by Mauldin et al. maintains the posterior face of the heel open and exposed to its external surroundings, thereby avoiding contact between the external shell of the orthopedic brace and the posterior face of the heel. This configuration is particularly advantageous in cases where there is a wound on the posterior face of the heel, such as when the wearer has undergone Achilles tendon surgery. Contact between the wound and the rigid surfaces of the external shell could irritate the wound, causing discomfort to the wearer and also prolonging the wound healing process.
The closed-heel configuration of the external shell exemplified by Grim et al. covers the posterior face of the heel. This configuration is particularly advantageous in cases where the wearer maintains an active regimen of everyday activities. The rigid surface of the external shell protects the heel in the same manner as conventional footwear to prevent potentially painful impacts against the heel by objects in the external surroundings during normal activity.
The present invention recognizes a need for an orthopedic walker boot having an external shell which can be transitioned from the closed-heel configuration to the open-heel configuration or vice versa at any time in accordance with the needs of the wearer. Accordingly, it is an object of the present invention to provide an improved orthopedic walker boot having an external shell which is readily adaptable to alternate configurations in accordance with the varying needs of the wearer. In particular, it is an object of the present invention to provide an orthopedic walker boot having an external shell which is readily adaptable to the closed-heel configuration or the open-heel configurations as desired. More particularly, it is an object of the present invention to provide an orthopedic walker boot having an external shell including a heel plate which is selectively removable by the practitioner so that the external shell adopts an open-heel configuration or which is selectively insertable by the practitioner so that the external shell adopts a closed-heel configuration.
Another common feature of the above-recited prior art orthopedic walker boots is that the external shell has an outer sole on the bottom thereof which functions as a walking platform for the foot of the wearer against the ground during normal activity. The outer sole of some of these prior art orthopedic walker boots is characterized as having an arcuate configuration. In particular, the outer sole is bowed upward along its longitudinal axis from the approximate midpoint of the external shell toward the heel and toe of the external shell. See, for example, Grim et al. and Payton.
The arcuate configuration of the outer sole is intended to enhance the ability of the wearer to walk with a more normal gait while wearing the orthopedic walker boot. In a typical normal walking gait, the heel strikes the ground first when the wearer takes a step. The foot of the wearer then flexes, the foot rolling forward along the ground with the heel disengaging the ground and the ball of the foot and toes engaging the ground. Thereafter, the entire foot disengages the ground to complete the step while the next step is simultaneously being initiated by a heel strike of the opposite foot. The outer sole on conventional footwear is generally sufficiently flexible to enable a person to roll the foot in the normal walking gait without requiring any curvature of the outer sole. However, the outer sole of prior art orthopedic walker boots are substantially bulkier and more rigid than the outer soles of conventional footwear. Therefore, the outer sole on the external shell of many prior art orthopedic walker boots is arced to facilitate the longitudinal rolling of the foot in the normal walking gait.
Although rolling of the foot along its longitudinal axis from heel to toe is an accurate characterization of the normal walking gait, the foot also rolls along its latitudinal axis, which is perpendicular to the longitudinal axis, from the medial to the lateral side of the foot or vice versa during a normal walking gait. The present invention further recognizes a need for an orthopedic walker boot having an external shell with an outer sole which is not only curved along its longitudinal axis, but is also curved along its latitudinal axis in a manner which facilitates both the longitudinal and latitudinal rolling of the foot in the normal walking gait.
Accordingly, in addition to the above-recited objects, it is an object of the present invention to provide an improved orthopedic walker boot having an external shell with an outer sole which is configured to facilitate the rolling of the foot in the normal walking gait. In particular, it is an object of the present invention to provide an improved orthopedic walker boot having an external shell with an outer sole which is curved along two different axes of its walking surface. More particularly, it is an object of the present invention to provide an orthopedic walker boot having an external shell with an outer sole which is curved along the longitudinal and latitudinal axes of its walking surface. These objects and others are accomplished in accordance with the invention described hereafter.